As evidenced by Japanese Utility Model No. 57989/1986 laid-open on Apr. 18, 1986, games using a liquid crystal display are known. In this game, a game cartridge, attachable to a main body, incorporates a game program and an operating system program to be executed by a central processing unit within the body. The main body also includes a liquid crystal display ("LCD") system.
The present invention provides unique method and apparatus for thwarting the use of unauthorized game cartridges in such a system. In this fashion, unauthorized game cartridges which contain copied programs or low quality programs may be precluded from being used in such a system. Additionally, unauthorized low quality game cartridges which may damage the main body over time (e.g., the connectors) are precluded from being used in the system.
Prior methods have heretofore been used for preventing unauthorized or copied programs from being executed by an information processing apparatus. One such system is disclosed in the Japanese Patent Publication No. 17849/1972 published on Oct. 18, 1972. In this system, a first method is disclosed wherein a first password is assigned to a specific information processing system to distinguish it from other information processing systems. The first password is compared with a second password which is assigned to a floppy disk having a program stored therein. The floppy disk is permitted to be used only when both passwords are identical.
A second method is disclosed in U.S. Pat. No. 4,462,076 issued on Jul. 24, 1984. In this method, data indicative of the proprietor of a copyright are respectively stored in a main memory unit and a cartridge memory. Such data is compared and, if there is a match, the proprietor data is simply displayed and thereafter a program stored in the cartridge memory may be executed.
A third method is disclosed in Japanese Patent Publication No. 18074/1984 published on Apr. 25, 1984. In this method, copy preventing information such as a trademark is stored in a plurality of semiconductor memories and, when a printed circuit board in which a program is copied is used, the copy preventing information is displayed on a CRT, thereby subjecting the copier to a possible claim of trademark infringement. Clearly, this third method is not effective where the copier deletes or changes the copy preventing information to thereby avoid any issue regarding the infringement of a trademark right.
The first and second methods are similar to each other in that they both permit the use of a floppy disk or a cartridge on the condition that first and second identifying data are coincident. However, the first method does not expressly teach that the password is displayed. Thus, the first method does not teach displaying information relating to the proprietor of the copyright as done in the second method.
In the second method, in the case where the proprietor data in the main unit memory and the proprietor data in the cartridge memory are not coincident, the cartridge cannot be used. However, since no proprietor data is displayed in this case, an operator or user will not be informed as why the cartridge cannot be used. Furthermore, if the results of the comparison indicate that the proprietor data matches, no further checks are made to insure that the cartridge is authorized.
Therefore, a principal object of the present invention is to provide an authentication system for an external memory unit, in which it is possible to more effectively prevent the use of unauthorized external memory units in a predetermined information processing system, such as a hand-held electronic video game system.
The present invention is directed to a system for preventing the unauthorized use of an external memory unit which is used in an information processing system comprising an external memory unit having an external memory which is attachably/detachably connected to an information processing apparatus capable of displaying a predetermined image on a display means in accordance with a program stored in the external memory when the external memory unit is loaded into the information processing apparatus. The information processing apparatus includes an information processing means capable of accessing a predetermined maximum address space; an internal memory having a first memory area which has a first memory space relatively smaller than the maximum address space and stores first character data for preventing the unauthorized use of the external memory unit and an authenticity determining program data for determining the authenticity of the external memory unit based upon the first character data; and a memory selecting means for changing or selecting one of the internal memory and the external memory. The external memory of the external memory unit includes a second memory area having a memory space corresponding to the first memory space and a third memory area having a relatively larger second memory space. In a portion of the third memory area of the external memory, second character data is stored which has a predetermined relationship with respect to the first character data stored in the internal memory. Additionally, a program for displaying an image in accordance with a predetermined purpose (e.g., an interactive game) is stored in at least the remaining memory area of the third memory area. When the external memory unit is loaded to the information processing apparatus, the memory selecting means sets the first memory space as the address space which the information processing means can access. Thereafter, the information processing means determines whether the first character data and the second character data have the predetermined relationship by executing the authenticity determining program data stored in the internal memory. If the first and second character data have the predetermined relationship, the memory selecting means selects the second memory space as the address space which the information processing means can access to allow the information processing means to have access to the external memory.
As indicated above, when the external memory unit is loaded to the information processing apparatus, the memory selecting means selects the first memory space as the address space which the information processing means can access. Thereafter, prior to any comparison operation, the second character data stored in the external memory is displayed on the display means. The authenticity determining program stored in the internal memory is then executed. At this time, the first and second character data are compared with each other in accordance with the authenticity determining program and, when it is determined that both character data have the predetermined relationship, the memory selecting means selects the external memory as a memory to which the information processing means can have access.
In one embodiment, the information processing apparatus is constructed as a hand-held electronic game machine which is intended to be operated while the machine is sandwiched by the player's hands. Such a hand-held electronic game machine includes a hand-held case; a first operation switch disposed at a position where it can be operated by the thumb of the left hand on a front surface of the case; a second operation switch disposed at a position where it can be operated by the thumb of the right hand on the front surface of the case; and a third operation switch provided in a region where an imaginary loci of the thumbs of the left hand and right hand intersect with each other on the front surface of the case.
A direction designating switch (specifically, a cross-key switch) which is utilized for designating a moving direction of a game character is arranged as the above described first operation switch, and an action key (specifically, a push-button switch) for designating one of various kinds of action or motion of the game character. For example, the depression of such a push-button switch may cause a game character to jump, use a weapon, throw a ball or the like. These first and second operation switches are usually operated during the game. The first and second operation switches are arranged at positions where they can be easily operated during game play.
The above-described third operation switch, may, for example, be a start switch for designating the start of the game and/or a select switch for selecting a mode of operation of the game. Such a third operation switch is arranged in a region where the imaginary loci of the thumbs of the both hands intersect each other. Therefore, the third operation switch is disposed to be readily operated by the thumb of either hand. Thus, the third switch may be operated during game play without requiring the user to change the position of the hands during the game.
These and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the embodiments of the present invention when taken in conjunction with the accompanying drawings.